Antioxidant and Antiapoptotic Polyphenols from Green Tea Extract Ameliorate CCl4-Induced Acute Liver Injury in Mice.
Chin J Integr Med
; 26(10): 736-744, 2020 Oct.
Article
in En
| MEDLINE
| ID: mdl-31768871
ABSTRACT
OBJECTIVE:
To investigate the phenolic composition, antioxidant properties, and hepatoprotective mechanisms of polyphenols from green tea extract (GTP) in carbon tetrachloride (CCl4)-induced acute liver injury mouse model.METHODS:
High-performance liquid chromatography was used to analyze the chemical composition of the extract. Antioxidant activity of GTP was assessed by O2â-, OHâ, DPPHâ, and ferric-reducing antioxidant power (FRAP) assay in vitro. Sixty Kunming mice were divided into 6 groups including control, model, low-, medium-, and high-doses GTP (200, 400, 800 mg/kg) and vitamin E (250 mg/kg) groups, 10 in each group. GTP and vitamin E were administered at a level of abovementioned doses twice per day for 7 days prior to exposure to a single injection of CCl4. Hepatoprotective effects of GTP were evaluated in a CCl4-induced mouse model of acute liver injury, using commercial enzyme linked immunosorbent assay kits, histopathological observation, terminal deoxynucleotidyl transferase-mediated dUTPNick-end labeling (TUNEL) assay and Western blot.RESULTS:
GTP contained 98.56 µg gallic acid equivalents per milligram extract total polyphenols, including epicatechingallate, epigallocatechin gallate, epicatechin, and epigallocatechin. Compared with the model group, low-, medium-, or high doses GTP significantly decreased serum levels of alanine aminotransferase and aspartate transaminase (P<0.01). Histopathological observation confirmed that pretreatment of GTP prevented swelling and necrosis in CCl4-exposed hepatocytes. Hepatoprotective effects of low-, medium-, and high-dose GTP were associated with eliminating free radicals and improving superoxide dismutase, catalase, and glutathione peroxidase activity in the liver. Additionally, low-, medium-, and high-dose GTP decreased cell apoptosis in the CCl4-exposed liver (P<0.01). Phosphorylated nuclear factor kappa-B (NF-κB), p53, Bcl-2 associated x protein/B-cell lymphoma/leukemia-2 gene, cytochrome C, and cleaved caspase-3 levels were downregulated compared with the model group (P<0.01).CONCLUSION:
GTP achieves hepatoprotective effects by improving hepatic antioxidant status and preventing cell apoptosis through caspase-3-dependent signaling pathways.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Tea
/
Plant Extracts
/
Apoptosis
/
Chemical and Drug Induced Liver Injury
/
Polyphenols
/
Antioxidants
Type of study:
Prognostic_studies
Limits:
Animals
Country/Region as subject:
Asia
Language:
En
Journal:
Chin J Integr Med
Journal subject:
TERAPIAS COMPLEMENTARES
Year:
2020
Document type:
Article
Affiliation country:
China